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multiplier value Enter the keywords multiplier to specify the number of packets that must be
missed in order to declare a session down. The range is from 3 to 50. The default is
3.
role [active |
passive]
Enter the role that the local system assumes:
● Active — The active system initiates the BFD session. Both systems can be
active for the same session.
● Passive — The passive system does not initiate a session. It only responds to
a request for session initialization from the active system.
The default is Active.
Defaults See Parameters
Command Modes INTERFACE
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
This command provides the flexibility to fine-tune the timer values based on individual interface needs
when ISIS BFD is configured in CONFIGURATION mode. Any timer values specified with this command
overrides timers set using the bfd all-neighbors command. Using the no form of this command
does not disable BFD if BFD is configured in CONFIGURATION mode.
To disable BFD on a specific interface while BFD is configured in CONFIGURATION mode, use the
keyword disable.
neighbor bfd
Explicitly enable a BFD session with a BGP neighbor or a BGP peer group.
Syntax
neighbor {ip-address | peer-group-name} bfd
Parameters
ip-address Enter the IP address of the BGP neighbor that you want to explicitly enable for
BFD sessions in dotted decimal format (A.B.C.D).
peer-group-name Enter the name of the peer group that you want to explicitly enable for BFD
sessions.
Defaults none
Command Modes ROUTER BGP
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
When you enable a BFD session with a specified BGP neighbor or peer group using the bfd neighbor
command, the default BFD session parameters are used (interval: 200 milliseconds, min_rx: 200
milliseconds, multiplier: 3 packets, and role: active) if you have not specified parameters with the bfd
neighbor command.
When you explicitly enable a BGP neighbor for a BFD session with the bfd neighbor command:
● The neighbor does not inherit the global BFD enable values configured with the bfd neighbor
command or configured for the peer group to which the neighbor belongs.
256 Bidirectional Forwarding Detection (BFD)